Friday, September 30, 2011

... to bring you the sad news of the death of the Constitution of the United States. The Constitution had been ailing for some time, with the extrajudicial arrest, imprisonment, and torture of people deemed by the President to be "enemy combatants." But never before has the U.S. actually executed one of its own citizens without even the pretense of due process. Until now.

Sir Thomas More: Yes! What would you do? Cut a great road through the law to get after the Devil?

William Roper: Yes, I'd cut down every law in England to do that!

Sir Thomas More: Oh? And when the last law was down, and the Devil turned 'round on you, where would you hide, Roper, the laws all being flat? This country is planted thick with laws, from coast to coast, Man's laws, not God's! And if you cut them down, and you're just the man to do it, do you really think you could stand upright in the winds that would blow then? Yes, I'd give the Devil benefit of law, for my own safety's sake!

It's about a quarter of a mile wide, has a population of under 3,000, and is accessible only by boat, which tends to keep out the much of the tourist riffraff. Burano is the very definition of charming. If you're ever in Venice I highly recommend hopping on the vaporetto and heading on over, especially if you get tired of the crowds in the Piazza San Marco.

[Administrative note: the cruise we're on is a little unusual in that it has no sea days at all, so finding time to write is going to be tough. I'm going to do my best to keep it up, but if the travelogue entries seem short and intermittent, that's why.]

The speed of light has been dubbed the "cosmic speed limit" by the popular press, but this is not quite right. It is more like the cosmic speed reference. Imagine you're in a car driving due West on interstate 40. Your speedometer says 60 MPH. How fast are you really going? The answer depends on your point of view. Relative to the surface of the earth you are going 60 MPH (assuming your speedometer is working). But relative to the center of the earth you are actually moving East (which is to say, backwards) at several hundred miles an hour. This is why you see the sun set even though you are driving towards it.

If you could drive fast enough, you could actually match your speed to the rotation of the earth and "stand still" relative to the sun. The earth would be zipping by underneath you, but the sun would always remain in the same place in the sky. Go a little faster still and you could watch the sun rise in the West.

Now, suppose you set up an experiment in your car to measure the speed of light. You mount a long tube on the roof. On the front of this tube is a shutter than you can open and close to let light in. On the back is a light sensor. You open the shutter and measure how long it takes for the light to reach the sensor. The length of the tube divided by that time is the speed of light.

It turns out that when you do this experiment, the mind-boggling result is that you get the exact same speed measurement for light no matter how fast or in what direction you are driving. The reason for this (as far as we know) is that space and time are not the distinct things that we intuitively imagine them to be, but are rather two facets of a single underlying reality called spacetime. We intuitively think of moving through space as a fundamentally different kind of phenomenon than moving through time, but this turns out not to be true. When we move through space we change the way we move through time. In particular, the "faster" you move through space, the "slower" you move through time (a phenomenon known as time dilation). When you move through space at the speed of light you stop moving through time. From the point of view of a photon moving through the tube on the roof of your car, it is simultaneously at the beginning and the end of the tube, and at all points in between. (Another way of saying the same thing is that as you move faster and faster, the distances between things in the direction you are moving begin to shrink, a phenomenon known as Lorenzian contraction. When you move at the speed of light, the distance between all points along your trajectory becomes (from your frame of reference) zero, which is why you can be everywhere along your trajectory at once.)

Another way to think about this: everything is always moving at the speed of light through spacetime. When you "move" (through space) you aren't really changing your velocity (through spacetime), you are only changing your direction of motion. It's exactly the same as turning the steering wheel in your car. If you drive at, say, 60 MPH according to your speedometer but turn a little to the north, you are now going slower in the east-west direction but faster in the north-south direction. If you turn all the way north, you "stop moving" in the east-west direction. Moving through spacetime is exactly like that. There is no accelerator, no brakes, only a steering wheel. If you are moving zero miles per hour through space then you are moving 1 second per second (the speed of light) through time. If you "turn the wheel" and start moving through space (north-south) then you will be moving slower through time (east-west). At the extreme you move through space at the speed of light and move through time at zero seconds per second (or zero miles per hour -- same thing).

Every single experiment that has ever been done has supported this view of the world. Until now.

If these results hold up it would not just be a little loophole in the laws of physics that somehow allows some esoteric subatomic particles to sneak past the cosmic radar detectors. It would be a fundamental violation of one of the two pillars of modern physics. It would also have potentially profound philosophical consequences. On our current view of physics, it is not merely impossible to move faster than light, it is actually non-sensical. To "move" faster than light you would actually have to travel backwards in time, which has all kinds of paradoxical consequences according to our current understanding of reality. I'm not saying this outcome is impossible, but it's unlikely.

Much more likely is some kind of experimental error. The difference in velocity of the supposedly superluminal neutrinos is only a few parts per million. This is well within the capabilities of modern technology to measure but it's not easy to do, and there are a lot of places that mistakes could sneak in. So far they haven't found any mistakes despite very careful scrutiny but that doesn't mean they won't. The last time experimental results seemed to violate relativity it took thirty years to figure out what was going on.

So my money is still on Einstein. But I'm not betting my entire life savings on it.

Wednesday, September 21, 2011

If you are a citizen of the United States there is blood on your hands tonight. When seven of nine eye-witnesses recant, when some of them allege being coerced by the police, when three of the jurors recant, when there is no physical evidence, what you are left with is not reasonable doubt, it is in fact no evidence whatsoever that Troy Davis killed anyone.

But none of that matters. What matters is that a white policeman was murdered. What matters is that the family is grieving. That cannot be allowed to stand. So after twenty years of appeal after appeal after appeal standing in the way of "justice", now at long last the final i has been dotted and the final t crossed. All of the protocols have been followed, all of the safeguards adhered to. The sunk cost invested in getting "justice" for Mark MacPhail is so high that to let Troy Davis live would be an unacceptable admission of the failings of the system we have built.

Make no mistake: we have failed. Someone killed Mark MacPhail, and whoever it was will now almost certainly never be known. Despite the appeals and the safeguards, the procedures and process, we almost certainly got the wrong guy. If you are a citizen of a democracy you can't blame that on the process, because the process is you.

Neither Troy Davis nor Mark MacPhail will get justice. Because the cost of that justice would be for us to admit we were wrong. And that is, apparently, too high a price to pay.

Thursday, September 15, 2011

In July of this year I made a purchase from an on-line vendor. Yesterday I got this letter from them:

The legalities of the situation are this: although the company is headquartered in Minnesota, they have a presence in California and so technically I should have been charged sales tax by the vendor. Since they didn't, it is now technically my responsibility to pay the equivalent amount in use tax. The sales tax rate varies depending on exactly where you live but in my case it's 8.25%. So the amount due is $2.05.

Which I would happily pay. The government where I live actually works pretty well, and I'm happy to pay my fair share to keep it up and running. But the problem is this: this particular vendor normally doesn't sell to consumers, they sell to small businesses, in which case no sales tax is due. So instead of just paying the $2.05 and charging it to my credit card, they want me to fill out this form:

Let's do a little math here. There are at least three human beings involved in this process: me, whoever at the company has to process the form when I send it back, and the auditor. Let's suppose that we each bill at $60 an hour, and that it takes each of us one minute to do our respective task in this little bit of economic kabuki theatre. So we have just effectively spent $3 to generate $2.05 worth of tax revenue.

This is another example of the societal failure to understand the difference between money and wealth. Somewhere in the government some bureaucrat has been charged with the task of collecting the money which the state is legally due with (apparently) no regard for the cost of doing the collecting. So the government will get its $2.05, but society will be $3 poorer for it. At least.

If this were an isolated incident it would not even be worth the bother to write about. But it isn't. This sort of short-sightedness pervades American society at every level, from people who choose their credit cards on the basis of which ones give them the most frequent-flyer miles to the weenies of Wall Street who continue to promulgate the myth that everyone can get rich by playing the stock market. (Hey, it worked for them, didn't it?)

And now I have to stop writing because I need to fill out this stupid form.

Saturday, September 10, 2011

Robert Reich in the NYT has a really good graphical summary of the historical trends in the U.S. economy. If there's any doubt in your mind that the U.S. is a stronger country when top marginal tax rates are higher, this should dispel it. This is about as close to a controlled experiment as you can get in macroeconomics.

Be sure to scroll all the way down, and pay particular attention to the middle of the chart, where the results are neatly summed up in one sentence:

"Great wealth for the top 1% was reversed by policy but then rose again." (Emphasis added.)

What Reich doesn't say, but I will, is that it rose again because of government policy. The chart makes an unfortunate concession to physical layout by putting the white line that separates the "great prosperity" from the "great regression" around 1978. But in fact if you look at the income disparity chart, the real divergence between the top 1% and the rest of the population didn't begin until about 1982, shortly after the Reagan tax cuts. That's either an extraordinary coincidence (one of these day's I'll do the math and figure out the actual odds), or there's a causal relationship.

The evidence could hardly be clearer: low marginal tax rates on top earners leads to massive income inequality, which leads to a collapse in demand, which leads to economic depression. At root the problem is, as I have been saying for a long time now, a fundamental failure at all levels of society to understand the difference between money and wealth, and in particular, a widespread belief that having more money is the same as having more wealth. It isn't. The end-game of our current trajectory is the devolution of the United States of America into a third-world country, complete with crumbling infrastructure, inflated currency, and ubiquitous poverty except inside the gated enclaves of the rich and powerful. Of course, these things take time -- decades -- to play out. But unless We (or perhaps I should say You) the People take steps to reel in the emerging American oligarchy, there is no reason to believe that it won't play out the same way it did the last time we did this experiment.

Wednesday, September 07, 2011

Huge crabs more than a metre across have invaded the Antarctic abyss, wiped out the local wildlife and now threaten to ruin ecosystems that have evolved over 14 million years.

Three years ago, researchers predicted that as the deep waters of the Southern Ocean warmed, king crabs would invade Antarctica within 100 years.

But video taken by a remotely operated submersible shows that more than a million Neolithodes yaldwyni have already colonised Palmer Deep, a basin that forms a hollow in the Antarctic Peninsula continental shelf.

They are laying waste to the landscape. Video footage taken by the submersible shows how the crabs prod, probe, gash and puncture delicate sediments with the tips of their long legs. "This is likely to alter sediment processes, such as the rate at which organic matter is buried, which will affect the diversity of animal communities living in the sediments," says Craig Smith of the University of Hawaii at Manoa, whose team discovered the scarlet invaders.

A woman in Las Cruces. New Mexico with no criminal record was subjected by police to a forcible body cavity search. The search turned up nothing, and the woman was not arrested. But she was charged. $1122 to be precise.

Monday, September 05, 2011

Following up on Don's post about religion-as-standard, it turns out that on a purely Darwinian analysis, group idiocy has survival value, and if there's enough of it around it can become an evolutionarily stable strategy. If idiocy exceeds a critical threshold, it can actually become irrational to act rationally. This should strike fear in the heart of Bayesians everywhere.

If ever there was proof that the hand of Loki is at work in the world, surely this is it.

Thursday, September 01, 2011

Ron occasionally writes about religion (vs. atheism) on this blog. He's had at least two excellent insights: First, that "deconverting" a religious believer has much more in common with drug rehab for an addict than it does with a rational, scientific debate. And second, promoting the idea that perhaps there is anall-powerful supernatural being controlling influencing our fates, but perhaps it is Loki the Trickster rather than some more benevolent god.

In a related vein, Robin Hanson at Overcoming Bias suggests that a good analogy for the possibility of a (widespread) transition from religion to atheism is the changing of any existing widespread industry standard. And, as numerous startups have learned to their dismay, there is enough inertia behind any widespread standard, that it isn't sufficient that your new idea is objectively better. It must be enough better (perhaps an order of magnitude) that the effort involved in the change has enough payoff to make it worthwhile for the customer.

At the moment, atheism is "right", but the benefits of being "right" on this subject (vs. just being an average, typical member of your society) are so minor, that the cost is rarely worth it. QWERTY is a poor keyboard layout, but hardly anyone uses a different one. Metric is a much better measurement system than the old English units, but even though most of the world changed, the USA didn't quite make it over the bar (aside from the military and medicine, where it could be mandated top-down). In much the same way, religion and society have co-adapted to work well enough together, that "atheism is better" may be true, but it isn't (yet) enough better.